(Windows, RPMs) Upgraded the included OpenSSL to version 1.0.1i. [Daniel Miller]

(Windows) Upgraded the included Python to version 2.7.8. [Daniel Miller]

Removed the External Entity Declaration from the DOCTYPE in Nmap's XML. This was added in 6.45, and resulted in trouble for Nmap XML parsers without network access, as well as increased traffic to Nmap's servers.

Nmap is an open source and cross-platform software that provides users with one of the most powerful network discovery and security auditing utility appreciated by numerous system administrators and security professionals around the world.

Features at a glance

Key features include the ability to monitor service and host uptime, manage service upgrade schedules, do network inventory, discover available hosts on a network based on raw IP packets, as well as to discover running services and operating systems on a specific network.

In addition, it supports a wide range of advanced network mapping techniques, including ping sweeps, TCP/UDP port scanning mechanisms, as well as the ability to scan networks of hundreds of thousands of computers.

Getting started with Nmap

It is a command-line only application that can be access only from a X11 terminal emulator application or the Linux console. Just type nmap and hit Enter to get a list of all its options, categorized by target specification, host discovery, scan techniques, and script scan.

In addition, it includes options for OS detection, timing and performance, server and version detection, firewall/IDS evasion and spoofing, port specification and scan order, and other.

Nmap was used on blockbuster movies at Hollywood

Another interesting fact about this piece of software is that it has been used in a dozen of blockbuster movies, such as Matrix Reloaded, Dredd, Elysium, Bourne Ultimatum, Die Hard 4, The Girl with the Dragon Tattoo, and G.I. Joe: Retaliation.

It also appeared in less popular movies and animations, including The Listening, Justice League: Doom, Abduction, Extracted, 13: Game of Death, Battle Royale, Broken Saints, Khottabych, Bloody Monday, and HaXXXor: No Longer Floppy.

Bottom line

All in all, Nmap is the most powerful network scanner utility for the GNU/Linux platform. It is used by numerous security professionals, as well as hackers around the world to discover vulnerabilities and secure entire networks from unwanted traffic.

Nmap was reviewed by Marius Nestor, last updated on January 10th, 2015